Technical Field
The present invention generally relates to an image projector and a method of controlling the image projector.
Description of the Related Art
The recent projectors, such as digital light processing (DLP) projectors with digital micro-mirror devices (DMDs), which are small and light, are widely used at offices and schools as well as at homes.
There are various developments for the projectors to achieve, for example, higher resolution of liquid crystal panels, improved efficiency in light sources such as lamps, and reduction in manufacturing costs. Among them, there is a need for reducing execution time, that is, the time counted from the time when the power of the projector is turned on to start lighting the lamp, to the time when the light level of the lamp reaches a sufficient level for projection, for example, as described in Japanese Patent Application Publication Nos. 2010-160195 and 2007-34263.
For example, Japanese Patent Application Publication No. 2007-34263 discloses an image display apparatus, which activates a power source circuit when pressing of a power key is detected, and sets a lamp ballast circuit with a preset voltage to start driving the lamp, thus reducing execution time of the image display apparatus. However, in order to detect pressing of the power key, a microcomputer that consumes relatively high power is kept turned on, thus increasing power consumption of the image display apparatus.